Photo Courtesy - Getty Images(NEW YORK) -- Ever since Madonna planted that wet kiss on Britney Spears in front of millions of television viewers at the 2003 MTV Video Music Awards, women have been loosening up sexually with other women.

These so-called flexisexuals say that although they are not gay or even bisexual, they enjoy flirting and kissing girls -- but they still enjoy having sex with men.

Experts say they may be influenced by the growing visibility of same-sex couples and more open attitudes about sex in general.

Pop culture, itself, seems to celebrate that flexibility in songs like Katy Perry's, "I Kissed a Girl," a song that 19-year-old Alisha Garrison said "made girls be more free to do whatever they want."

"It's not really experimenting, but maybe trying to get some attention," said Garrison, an urban planning student from Simi Valley, Calif.

Perry admits in her lyrics, "I got so brave, drink in hand, I lost my discretion."

Flexisexual is also known as heteroflexible, pansexual or queer, all subtle variations that mean they are not closing any doors.

Women say it has has more to do with their view of the world than their practice in the bedroom.

"When I was younger, girls bounced around in high school about sexuality," said Jamilla Wright, a public relations major at the University of Texas. "I think the older we get the more comfortable we are with it being based more on the individual than either-or as far as sexuality is concerned."

"Labels matter less," said the 21-year-old.

Hollywood has its own examples: Lindsay Lohan, 24, who dated Samantha Ronson, denied she was a lesbian and "maybe" bisexual. She has since returned to men.

Angelina Jolie, 35 and now happily ensconced with Brad Pitt, had a sexual relationship with Jenny Shimizu. And Drew Barrymore, 35, has reportedly said, "Being with a woman is like exploring your own body, but through someone else."

Flexisexual.net is a website where women can find "sexy, open-minded women looking to explore their sexuality, chat, hook up with and more."

"This is where straight women who feel curious about bisexual passion or romance start out," it says. "The common interest makes it easy for like-minded individuals to connect with each other and find someone compatible, compared to leaving it up to chance."

For many of today's women in their late teens and 20s, openness to intimate physical relationships with either gender has become a way of life, rather than an "experiment."

This relatively new phenomenon is likely a product of a generation unconcerned with labels. Often, it begins in the enlightened college cocoon, where women can explore their sexuality, though a recent ABC report from San Antonio, Texas, said flexisexuality is also part of the high school culture.

Experts say more sexual experimentation occurs when people have not yet found a partner, before they settle into monogamous relationships. College is also a safe cocoon for self-discovery.